This section is intended to provide a background or context to the disclosed embodiments. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived or pursued. Therefore, unless otherwise indicated herein, what is described in this section is not prior art to the description and claims in this application and is not admitted to be prior art by inclusion in this section.
Conventional wireless networks are configured with multiple, geographically dispersed antennas (access points), serving multi-sector cells and connected to a central baseband processing unit, whereby communication links with a mobile device (user equipment, or UE) can be transferred between sectors served by a single access point and handed-off between adjacent sectors served by different access points. This configuration of network topology and control lends itself to the use of coordinated multi-point transmission (CoMP) to improve signal quality and to increase data rates. Coordinating the transmission from multiple geographically dispersed access points can be used to increase the signal-to-noise ratio at a UE.
For example, coordinated multi-point transmission is considered for LTE-Advanced wireless communication systems by 3rd Generation Partnership Project (3GPP) Technical Requirement TR 36.814, “Further Advancements for E-UTRA Physical Layer Aspects (Release 9)”, to improve cell edge data throughput and average spectral efficiency. One proposed type of CoMP is Joint Processing/Transmission (JP/T) where multiple access points, serving a cluster of contiguous sectors, transmit data to a single CoMP capable UE using the same physical resource block (PRB), where for LTE-Advanced a PRB is defined as a particular set of OFDM (orthogonal frequency division multiplex) sub-carriers in a designated time slot, using RAKE receiver technology to combine signals with different arrival times. The allocation of the same physical resource block to a UE from multiple access points serves to improve the signal quality at the UE being served by CoMP-JP/T, but the allocated PRBs are not available to serve other UEs in the cluster of sectors because there is no mechanism for the reallocation of the PRBs to UEs in sectors of the cluster served by other access points.